Description: Do not use pickle for serialization in memcache, but JSON We don't want to use pickle as it can execute arbitrary code. JSON is safer. However, note that it supports serialization for only some specific subset of object types; this should be enough for what we need, though. . To avoid issues on upgrades (unability to read pickled values, and cache poisoning for old servers not understanding JSON), we add a memcache_serialization_support configuration option, with the following values: . 0 = older, insecure pickle serialization 1 = json serialization but pickles can still be read (still insecure) 2 = json serialization only (secure and the default) . To avoid an instant full cache flush, existing installations should upgrade with 0, then set to 1 and reload, then after some time (24 hours) set to 2 and reload. Support for 0 and 1 will be removed in future versions. Origin: upstream Bug-Debian: http://bugs.debian.org/686812 Bug-Ubuntu: https://launchpad.net/bugs/1006414 --- swift-1.4.8.orig/etc/memcache.conf-sample +++ swift-1.4.8/etc/memcache.conf-sample @@ -3,3 +3,13 @@ # several other conf files under [filter:cache] for example. You can specify # multiple servers separated with commas, as in: 10.1.2.3:11211,10.1.2.4:11211 # memcache_servers = 127.0.0.1:11211 +# +# Sets how memcache values are serialized and deserialized: +# 0 = older, insecure pickle serialization +# 1 = json serialization but pickles can still be read (still insecure) +# 2 = json serialization only (secure and the default) +# To avoid an instant full cache flush, existing installations should +# upgrade with 0, then set to 1 and reload, then after some time (24 hours) +# set to 2 and reload. +# In the future, the ability to use pickle serialization will be removed. +# memcache_serialization_support = 2 --- swift-1.4.8.orig/etc/proxy-server.conf-sample +++ swift-1.4.8/etc/proxy-server.conf-sample @@ -122,6 +122,18 @@ use = egg:swift#memcache # default to the value below. You can specify multiple servers separated with # commas, as in: 10.1.2.3:11211,10.1.2.4:11211 # memcache_servers = 127.0.0.1:11211 +# +# Sets how memcache values are serialized and deserialized: +# 0 = older, insecure pickle serialization +# 1 = json serialization but pickles can still be read (still insecure) +# 2 = json serialization only (secure and the default) +# If not set here, the value for memcache_serialization_support will be read +# from /etc/swift/memcache.conf (see memcache.conf-sample). +# To avoid an instant full cache flush, existing installations should +# upgrade with 0, then set to 1 and reload, then after some time (24 hours) +# set to 2 and reload. +# In the future, the ability to use pickle serialization will be removed. +# memcache_serialization_support = 2 [filter:ratelimit] use = egg:swift#ratelimit --- swift-1.4.8.orig/doc/manpages/proxy-server.conf.5 +++ swift-1.4.8/doc/manpages/proxy-server.conf.5 @@ -205,6 +205,21 @@ Enables the ability to log request heade .IP \fBmemcache_servers\fR The memcache servers that are available. This can be a list separated by commas. The default is 127.0.0.1:11211. +.IP \fBmemcache_serialization_support\fR +This sets how memcache values are serialized and deserialized: +.RE + +.PD 0 +.RS 10 +.IP "0 = older, insecure pickle serialization" +.IP "1 = json serialization but pickles can still be read (still insecure)" +.IP "2 = json serialization only (secure and the default)" +.RE + +.RS 10 +To avoid an instant full cache flush, existing installations should upgrade with 0, then set to 1 and reload, then after some time (24 hours) set to 2 and reload. In the future, the ability to use pickle serialization will be removed. + +If not set in the configuration file, the value for memcache_serialization_support will be read from /etc/swift/memcache.conf if it exists (see memcache.conf-sample). Otherwise, the default value as indicated above will be used. .RE --- swift-1.4.8.orig/swift/common/memcached.py +++ swift-1.4.8/swift/common/memcached.py @@ -27,11 +27,17 @@ import time from bisect import bisect from hashlib import md5 +try: + import simplejson as json +except ImportError: + import json + DEFAULT_MEMCACHED_PORT = 11211 CONN_TIMEOUT = 0.3 IO_TIMEOUT = 2.0 PICKLE_FLAG = 1 +JSON_FLAG = 2 NODE_WEIGHT = 50 PICKLE_PROTOCOL = 2 TRY_COUNT = 3 @@ -57,7 +63,8 @@ class MemcacheRing(object): """ def __init__(self, servers, connect_timeout=CONN_TIMEOUT, - io_timeout=IO_TIMEOUT, tries=TRY_COUNT): + io_timeout=IO_TIMEOUT, tries=TRY_COUNT, + allow_pickle=False, allow_unpickle=False): self._ring = {} self._errors = dict(((serv, []) for serv in servers)) self._error_limited = dict(((serv, 0) for serv in servers)) @@ -69,6 +76,8 @@ class MemcacheRing(object): self._client_cache = dict(((server, []) for server in servers)) self._connect_timeout = connect_timeout self._io_timeout = io_timeout + self._allow_pickle = allow_pickle + self._allow_unpickle = allow_unpickle or allow_pickle def _exception_occurred(self, server, e, action='talking'): if isinstance(e, socket.timeout): @@ -130,16 +139,21 @@ class MemcacheRing(object): :param key: key :param value: value - :param serialize: if True, value is pickled before sending to memcache + :param serialize: if True, value is serialized with JSON before sending + to memcache, or with pickle if configured to use + pickle instead of JSON (to avoid cache poisoning) :param timeout: ttl in memcache """ key = md5hash(key) if timeout > 0: timeout += time.time() flags = 0 - if serialize: + if serialize and self._allow_pickle: value = pickle.dumps(value, PICKLE_PROTOCOL) flags |= PICKLE_FLAG + elif serialize: + value = json.dumps(value) + flags |= JSON_FLAG for (server, fp, sock) in self._get_conns(key): try: sock.sendall('set %s %d %d %s noreply\r\n%s\r\n' % \ @@ -151,8 +165,9 @@ class MemcacheRing(object): def get(self, key): """ - Gets the object specified by key. It will also unpickle the object - before returning if it is pickled in memcache. + Gets the object specified by key. It will also unserialize the object + before returning if it is serialized in memcache with JSON, or if it + is pickled and unpickling is allowed. :param key: key :returns: value of the key in memcache @@ -168,7 +183,12 @@ class MemcacheRing(object): size = int(line[3]) value = fp.read(size) if int(line[2]) & PICKLE_FLAG: - value = pickle.loads(value) + if self._allow_unpickle: + value = pickle.loads(value) + else: + value = None + elif int(line[2]) & JSON_FLAG: + value = json.loads(value) fp.readline() line = fp.readline().strip().split() self._return_conn(server, fp, sock) @@ -258,7 +278,9 @@ class MemcacheRing(object): :param mapping: dictonary of keys and values to be set in memcache :param servery_key: key to use in determining which server in the ring is used - :param serialize: if True, value is pickled before sending to memcache + :param serialize: if True, value is serialized with JSON before sending + to memcache, or with pickle if configured to use + pickle instead of JSON (to avoid cache poisoning) :param timeout: ttl for memcache """ server_key = md5hash(server_key) @@ -268,9 +290,12 @@ class MemcacheRing(object): for key, value in mapping.iteritems(): key = md5hash(key) flags = 0 - if serialize: + if serialize and self._allow_pickle: value = pickle.dumps(value, PICKLE_PROTOCOL) flags |= PICKLE_FLAG + elif serialize: + value = json.dumps(value) + flags |= JSON_FLAG msg += ('set %s %d %d %s noreply\r\n%s\r\n' % (key, flags, timeout, len(value), value)) for (server, fp, sock) in self._get_conns(server_key): @@ -302,7 +327,12 @@ class MemcacheRing(object): size = int(line[3]) value = fp.read(size) if int(line[2]) & PICKLE_FLAG: - value = pickle.loads(value) + if self._allow_unpickle: + value = pickle.loads(value) + else: + value = None + elif int(line[2]) & JSON_FLAG: + value = json.loads(value) responses[line[1]] = value fp.readline() line = fp.readline().strip().split() --- swift-1.4.8.orig/swift/common/middleware/memcache.py +++ swift-1.4.8/swift/common/middleware/memcache.py @@ -27,20 +27,36 @@ class MemcacheMiddleware(object): def __init__(self, app, conf): self.app = app self.memcache_servers = conf.get('memcache_servers') - if not self.memcache_servers: + serialization_format = conf.get('memcache_serialization_support') + + if not self.memcache_servers or serialization_format is None: path = os.path.join(conf.get('swift_dir', '/etc/swift'), 'memcache.conf') memcache_conf = ConfigParser() if memcache_conf.read(path): - try: - self.memcache_servers = \ - memcache_conf.get('memcache', 'memcache_servers') - except (NoSectionError, NoOptionError): - pass + if not self.memcache_servers: + try: + self.memcache_servers = \ + memcache_conf.get('memcache', 'memcache_servers') + except (NoSectionError, NoOptionError): + pass + if serialization_format is None: + try: + serialization_format = \ + memcache_conf.get('memcache', + 'memcache_serialization_support') + except (NoSectionError, NoOptionError): + pass + if not self.memcache_servers: self.memcache_servers = '127.0.0.1:11211' + if serialization_format is None: + serialization_format = 2 + self.memcache = MemcacheRing( - [s.strip() for s in self.memcache_servers.split(',') if s.strip()]) + [s.strip() for s in self.memcache_servers.split(',') if s.strip()], + allow_pickle=(serialization_format == 0), + allow_unpickle=(serialization_format <= 1)) def __call__(self, env, start_response): env['swift.cache'] = self.memcache --- swift-1.4.8.orig/test/unit/common/test_memcached.py +++ swift-1.4.8/test/unit/common/test_memcached.py @@ -1,3 +1,4 @@ + # -*- coding: utf8 -*- # Copyright (c) 2010-2012 OpenStack, LLC. # # Licensed under the Apache License, Version 2.0 (the "License"); @@ -166,6 +167,9 @@ class TestMemcached(unittest.TestCase): self.assertEquals(memcache_client.get('some_key'), [1, 2, 3]) memcache_client.set('some_key', [4, 5, 6]) self.assertEquals(memcache_client.get('some_key'), [4, 5, 6]) + memcache_client.set('some_key', ['simple str', 'utf8 str éà']) + # As per http://wiki.openstack.org/encoding, we should expect to have unicode + self.assertEquals(memcache_client.get('some_key'), ['simple str', u'utf8 str éà']) self.assert_(float(mock.cache.values()[0][1]) == 0) esttimeout = time.time() + 10 memcache_client.set('some_key', [1, 2, 3], timeout=10) @@ -244,6 +248,24 @@ class TestMemcached(unittest.TestCase): self.assertEquals(memcache_client.get_multi(('some_key2', 'some_key1', 'not_exists'), 'multi_key'), [[4, 5, 6], [1, 2, 3], None]) + def test_serialization(self): + memcache_client = memcached.MemcacheRing(['1.2.3.4:11211'], + allow_pickle=True) + mock = MockMemcached() + memcache_client._client_cache['1.2.3.4:11211'] = [(mock, mock)] * 2 + memcache_client.set('some_key', [1, 2, 3]) + self.assertEquals(memcache_client.get('some_key'), [1, 2, 3]) + memcache_client._allow_pickle = False + memcache_client._allow_unpickle = True + self.assertEquals(memcache_client.get('some_key'), [1, 2, 3]) + memcache_client._allow_unpickle = False + self.assertEquals(memcache_client.get('some_key'), None) + memcache_client.set('some_key', [1, 2, 3]) + self.assertEquals(memcache_client.get('some_key'), [1, 2, 3]) + memcache_client._allow_unpickle = True + self.assertEquals(memcache_client.get('some_key'), [1, 2, 3]) + memcache_client._allow_pickle = True + self.assertEquals(memcache_client.get('some_key'), [1, 2, 3]) if __name__ == '__main__': unittest.main() --- swift-1.4.8.orig/test/unit/common/middleware/test_memcache.py +++ swift-1.4.8/test/unit/common/middleware/test_memcache.py @@ -47,6 +47,8 @@ class SetConfigParser(object): if section == 'memcache': if option == 'memcache_servers': return '1.2.3.4:5' + elif option == 'memcache_serialization_support': + return '2' else: raise NoOptionError(option) else: @@ -86,7 +88,8 @@ class TestCacheMiddleware(unittest.TestC exc = None try: app = memcache.MemcacheMiddleware( - FakeApp(), {'memcache_servers': '1.2.3.4:5'}) + FakeApp(), {'memcache_servers': '1.2.3.4:5', + 'memcache_serialization_support': '2'}) except Exception, err: exc = err finally: